Modern cars inject extra fuel to heat up the catalytic converter fast so it becomes functional. All ICE suck for the first 5-10 miles so I'm not at all surprised at that reading.Seems a little low.
You would figure the engine wouldn't run so rich while cold (30 degrees F) - (more fuel = lower combustion temperatures). Only drive one or two miles in ERDTT (for about 5 minutes) but, what a hit to MPG.
I'm thinking the gas "guess-O-meter" may be off and needs to recalibrate.
I've watched my Gen 1 tank down to 10mpg like it was pushed off a cliff, then work it's way back up to reasonable as the engine gets warm.